Domain names are evaluated according
to the standards RFC1034,
section 3, and RFC1123,
section 2.1. No accommodation is provided for the specialized needs of
other applications; if the domain name has been URL-encoded, for example,
validation will fail even though the equivalent plaintext version of the
same name would have passed.

Validation is also provided for top-level domains (TLDs) as defined and
maintained by the Internet Assigned Numbers Authority (IANA):